Pregnant women require observation for new, existing ocular conditions

Ocular problems may arise during pregnancy; existing conditions can worsen or ameliorate. Medication should be administered carefully.

Pregnancy affects women on many levels, and ophthalmologists should be aware of this condition’s effect on the health of women’s eyes.

“There are numerous physiologic changes that occur during pregnancy that can have both pathologic and nonpathologic effects on the eye, and ocular disorders may occur as a complication of pregnancy,” Elizabeth A. Davis, MD, FACS, told Ocular Surgery News.

Dr. Davis added, “In contrast, pregnancy may ameliorate certain other ocular conditions, and management and treatment of these disorders may differ between pregnant and nonpregnant patients.”

Exams and surface problems

Women should be examined during pregnancy to maintain their ocular health and catch any complications early.

“Pregnancy can cause new issues, new symptoms, new findings in their eyes,” Dr. Davis said. “For those who are otherwise healthy and not having problems, they probably need an exam once during the pregnancy and once after delivery.”

Others, though, who already have ocular complications, must be more closely monitored during pregnancy.

“For women with pre-existing ocular conditions, an examination at a minimum of every trimester is necessary and then soon after delivery,” Dr. Davis said.

Some of the easiest diagnoses to see in pregnant women are the changes that occur in their tear film.

“There is an increase in lysozyme, which is one of the viscous components of the tear film,” Dr. Davis said. “Along with a known generalized edema in pregnancy, there can be some increased thickness of the cornea, along with an increase in corneal curvature.”

Some studies have also documented some decreased corneal sensitivity during the pregnancy, she added.

This corneal desensitivity and other surface changes can also lead to contact lens intolerance, Janine Smith, MD, told Ocular Surgery News.

“The theory is that the corneal sensation decreases, the corneal thickness may increase, the corneal curvature may change, and all those may lead to contact lens intolerance,” she said. “It’s not uncommon for somebody to not tolerate their contact lenses during pregnancy or have a change in their contact lens prescription.”

Pregnancy-related disorders

Changes in a woman’s body during pregnancy can result in complications for her eyes, ones that appear solely because of her condition and often disappear after delivery.

Krukenberg’s spindle, for example, is a pigmentary disorder that afflicts mainly men, but progesterone levels rise sharply during pregnancy, increasing stromal melanin phagocytosis.

Elizabeth A. Davis

“Krukenberg’s spindle, which is found in pigment dispersion, has been noted to disappear after pregnancy, and it is thought that this may be due to the fact that several hormones of pregnancy have been demonstrated to increase pigment clearance,” Dr. Davis said.

Pregnancy is also “a hyper coagulable state,” and can cause vascular occlusions, according to Dr. Davis.

“There have been reports of both branch and central retinal artery occlusions either during pregnancy or in the immediate postpartum period,” she said. “There have also been reports of retinal vein occlusions in pregnancy, but they’re less common than retinal arterial occlusions.”

Although these disorders are also seen outside of pregnancy in both men and women, pregnancy presents the unique complication of amniotic fluid embolism, Dr. Davis said.

This problem results from amniotic fluid being introduced into the systemic circulation, resulting in anaphylaxis and a disseminated intravascular coagulopathy.

“That’s a serious complication of pregnancy and has a high mortality rate,” she said. “It can lead to bilateral retinal arterial occlusions with significant loss of vision.”

Lastly, central serous retinopathy (CSR) can occur during pregnancy, Bhavna P. Sheth, MD, said. “There may be conditions that are particularly associated with pregnancy or exacerbated by pregnancy.” CSR is characterized by a serous retinal detachment, causing blurred vision and metamorphopsia.

“The etiology is unknown,” she said. “But, interestingly, these women are more likely to have subretinal exudates, which can also be seen when CSR occurs outside of pregnancy, but is more common during pregnancy.

“Observation is recommended because, fortunately, the natural history is that it resolves near the end of pregnancy or during the postpartum period and usually the diagnosis can be made clinically, so a fluorescein angiogram is not absolutely necessary,” Dr. Sheth said.

Preeclampsia and eclampsia

In addition to those disorders, Drs. Davis and Sheth noted that preeclampsia and eclampsia are pregnancy-related conditions that can have ocular effects.

Some women suffer from preeclampsia and eclampsia, also known as pregnancy-induced hypertension. Dr. Sheth said this condition occurs in about 5% of pregnancies.

“Pregnancy-induced hypertension is a systemic hypertensive disorder where the patient has generalized edema and/or proteinuria during the third trimester of pregnancy,” Dr. Davis said. “That alone is preeclampsia, but if they develop seizures, then it’s called eclampsia.”

Ocular complications associated with this condition are common, she added. Studies have reported that 30% to 100% of preeclampsia and eclampsia patients have ocular involvement.

“Patients can have blurry vision, photopsias, scotomata, diplopia and even cortical blindness,” Dr. Davis said. “On examination, the most frequent finding is narrowing of the retinal arteries. Sometimes there can be hemorrhages.”

Dr. Sheth said in addition to these changes in the retinal arteries, serous retinal detachments or, rarely, an ischemic optic neuropathy could occur.

Hypertensive retinopathy is also a possible complication, Dr. Smith said, causing retinal edema and serious retinal detachments.

“Those things can be measured well now and quantified with optical coherence tomography,” and allows an ophthalmologist to avoid fluorescein angiography, she said.

“Fortunately, many of these signs will resolve and the vision does recover after the delivery or during the postpartum period,” Dr. Sheth added.

Existing conditions

Not only can pregnancy incite certain conditions in women’s eyes, but also previously existing conditions can be affected by pregnancy. Some are exacerbated and others are ameliorated, but flare up in the postpartum period.

“If [women] have pre-existing eye conditions, they need to be monitored more closely during pregnancy or in the early postpartum period,” Dr. Davis said.

Dr. Davis said many patients will ask their ophthalmologist, before becoming pregnant, about the complications of existing conditions.

Autoimmune diseases, for example, tend to be affected by pregnancy, which can further ocular complications of those diseases.

“Pregnancy appears to improve the systemic manifestation of sarcoidosis, but then [women] can have a significant relapse after they deliver,” Dr. Davis said. “Juvenile rheumatoid arthritis patients can show improvement of their systemic systems in pregnancy, but there’s a 59% chance of a postpartum flare-up.”

Lastly, multiple sclerosis stabilizes or improves during pregnancy, but several studies showed significantly increased risk of relapse after delivery, with an incidence of about 20% to 40%. The overall course of multiple sclerosis, though, seems unaffected, Dr. Davis said.

Ocularly, pre-existing glaucoma has been reported to improve in pregnant women, something Dr. Davis attributed to increased aqueous outflow.

“Although aqueous production seems to be stable during pregnancy, there is actually an increased facility of aqueous outflow in pregnant patients,” Dr. Davis said. “After delivery, a lot of this reverts back to normal.”

Diabetic retinopathy

One ocular condition that reacts adversely to pregnancy is diabetic retinopathy, although, Dr. Sheth said, the worsening depends upon the previous state of the disease.

“The most important thing that ophthalmologists need to be aware of is the risk of progression of diabetic retinopathy during pregnancy,” Dr. Sheth said.

She said progression is more likely in pregnant women who already have retinopathy at baseline. The studies vary, but the rates of development of progression range from 16% to 85% over the course of pregnancy, she said.

“There are various risk factors for progression,” she said, pointing toward pregnancy itself, the duration of diabetes, glycemic control and the amount of disease at baseline.

“It’s preferable to treat severe nonproliferative or proliferative diabetic retinopathy either before pregnancy or as soon as it develops during pregnancy,” Dr. Davis said. “[Pregnant patients] need frequent observation for their diabetic retinopathy.”

Dr. Sheth said the American Academy of Ophthalmology publishes general guidelines on how to monitor the pregnant diabetic during pregnancy.

“Ideally, they recommend an exam prior to conception or early in the first trimester, and then follow-up examinations would be at the discretion of the ophthalmologist,” she said. “In patients with no retinopathy or mild to moderate retinopathy, they may need an exam every 3 to 12 months and those with severe nonproliferative retinopathy may require an exam every 1 to 3 months.”

The postpartum period is unusual in that there is a high rate of spontaneous regression of diabetic retinopathy, Dr. Sheth added.

Ocular medications

A major concern for many ophthalmologists who examine pregnant patients is the possible toxicity that could be caused by ocular medications. Drs. Sheth and Davis advised that one should be aware of the possibilities and limit medication as needed.

“The question always comes up about ocular medications: a woman’s pregnant, what eye drops can you give without risking injury to the fetus?” Dr. Davis said. “Little is known about the risk of ophthalmic medications in pregnant and nursing women.”

Dr. Davis discussed the specific drugs that pose a threat to pregnant women and their unborn children.

“Beta-blockers, like timolol, should be avoided or used in the lowest dose in the first trimester of pregnancy,” she said. “Carbonic anhydrase inhibitors can have a potential teratogenic effect when administered during pregnancy and should be avoided when possible. Mydriatic, dilating agents have a potential teratogenic effect, as well as adverse fetal systemic effects, so they should only be administered during pregnancy when necessary.”

Dr. Davis said topical corticosteroids do not seem to pose a teratogenic risk, but should be used minimally. Erythromycin and polymyxin B were on her list of the safest antibiotics during pregnancy and lactation.

Antivirals, though, have been shown to be teratogenic in animals, she said. In addition, some studies have shown teratogenicity for sodium fluorescein.

“Can you do a fluorescein angiogram in a pregnant patient?” Dr. Davis asked. “Sodium fluorescein has been shown in rats to cross the placenta into fetal tissues and amniotic fluid. However, no teratogenic effects have been reported in other animals or in humans.”

Overall, Drs. Davis and Sheth agreed that adjustments must be made for pregnant women in an ophthalmologist’s office.

“Although there have been no reports with use of topical dilating drugs, all routine and nonessential ocular medications should probably be avoided in pregnancy,” Dr. Sheth said. “If they do need to dilate the eyes because of monitoring for a condition such as diabetic retinopathy, then probably using the lowest dose of the medication, for example, tropicamide a half a percent, and then advising the patient to perform nasal lacrimal sac occlusion to decrease the systemic absorption of the medication would be important.”

For more information:

• Elizabeth A. Davis, MD, FACS, can be reached at Minnesota Eye Consultants, 9117 Lyndale Ave. S., Bloomington, MN 55420; 952-888-5800; fax: 952-885-9942; e-mail: eadavis@mneye.com.
• Bhavna P. Sheth, MD, can be reached at The Eye Institute, 925 N. 87th St., Milwaukee, WI 53226; 414-456-2020; fax: 414-456-6300; e-mail: bsheth@mcw.edu.

• Katrina Altersitz is an OSN Staff Writer who covers all aspects of ophthalmology.