Approximately one half of all patients with cystic fibrosis (CF) are adults and, as life expectancy increases, issues of sexuality and reproduction become more common. A review by Liaschko and Koren discusses the effect of pregnancy on the mother and fetus when the mother has CF.
Many women with CF choose not to have children because of the genetic implications. All husbands or partners of women with CF should be offered genetic screening as part of comprehensive genetic counseling because carrier rates are very high in some populations of northern European descent. Families should be warned that tests are not completely reliable, because more than 500 different mutations are associated with clinical CF, and testing only detects the most common. For the same reason, antenatal testing can give false-negative results.
There is no evidence that pregnancy accelerates CF progression clinically or as assessed by changes in forced expiratory volume in one second (FEV1). Individual patients may, however, develop serious complications such as pulmonary hypertension or cor pulmonale. Pregnant patients with CF should continue physiotherapy and medication use with adjustment for physiologic changes of pregnancy and concerns about adverse effects on the fetus. Most antibiotics such as penicillins, cyclosporines, and aminoglycosides can be used safely during pregnancy, but tetracyclines should be avoided. Quinolones have not been shown to be teratogenic. Nearly all beta-adrenergic agonists can be used safely during pregnancy. Maternal hypoxia should be avoided because this can lead to fetal growth restriction.
Attention must also be given to maternal nutrition. Patients with CF usually have low weight gain during pregnancy. The additional demands of pregnancy may exacerbate malabsorption, gut motility disorders, diabetes, and hepatobiliary disease associated with CF. Ideally, all patients with CF should be referred to specialized teams for pregnancy management.
Opiates and general anesthesia should be avoided during delivery, and epidural anesthesia should be used if analgesia is required. Efforts should be made to avoid prolonged labor, which can exhaust the mother with CF. If necessary, early intervention with instrumental delivery is appropriate.
The outcome of pregnancy appears to depend largely on the health of the mother before she became pregnant. No increase in fetal malformations has been reported, and rates of preterm birth have ranged from 5.9 to 35 percent. Patients with FEV1 greater than 80 percent and no Burkholderia cepacia colonization have better outcomes, fewer operative deliveries, and lower rates of preterm birth than more seriously handicapped patients with CF. Pregnancy is likely to be complicated if the mother has pulmonary hypertension, cor pulmonale, or FEV1 less than 50 percent.
Breastfeeding should only be discouraged if the mother's health is poor. Breast milk from mothers with CF has a lower than normal fat content and lower levels of essential fatty acids, but it does not contain excessive sodium as previously believed.
Finally, parents with CF must address the implications of shortened life expectancy. Healthy parenting by people with chronic diseases includes preparation for child rearing and family support when the parent with CF becomes significantly disabled or dies.