Kidney Clinic - Baby talk

Life with chronic kidney disease (CKD) is full of questions: how long before my kidneys fail? Can I have a transplant? Which sort of dialysis should I choose? Can I dialyse at home? And some women also wonder whether they can, or should, have children. The good news is that, by planning ahead, many women with kidney disease can become pregnant and have a healthy baby.

“Today very few women with kidney disease are advised not to get pregnant, and even then, it’s up to a woman and her partner to decide. But it makes sense for any woman with kidney disease, who is thinking of becoming pregnant, to be aware of any possible problems and to discuss them in advance with her doctors,” says Professor Liz Lightstone. Liz is Professor of Renal Medicine at Imperial College, London, and has a special interest in pregnancy in CKD.

Planning for pregnancy

Any decision about pregnancy depends on a woman’s age and fertility, but timing is especially important if she has CKD. Generally, the better a woman’s kidney function, the better her and her baby’s outcomes. So doctors recommend an earlier pregnancy if kidney disease is likely to progress over time, while it is better to wait for symptoms to settle down if a woman has a disease like lupus that flares up.

Effective contraception is therefore key for women with kidney disease. Liz advises: “Each woman needs individualised advice about contraception, but long-acting methods like the progesterone implant or Mirena coil are much more reliable than condoms, which have a high failure rate even with ‘perfect’ use.”

A woman with kidney disease should plan to have her baby at a hospital with specialists in obstetrics and neonatal care, as well kidney specialists. “We now realise that even comparatively early CKD can influence the outcome of a pregnancy and increase the risk of conditions like pre-eclampsia,” explains Liz.

Pre-eclampsia usually occurs after 20 weeks of pregnancy, and is detected by a combination of high blood pressure and protein in the urine. Since delivering the baby is the only cure for pre-eclampsia, women with this condition are more likely to have a premature baby who therefore has a higher risk of poor outcomes.

Another reason for careful planning is that some medicines commonly used in kidney disease should not be taken during pregnancy. These medicines include the immune-suppressants cyclosphosphamide, methotrexate and mycophenolate, as well as rituximab and belimumab. ACE inhibitors like ramipril and lisinopril and ‘ARBs’ like losartan and irbesartan are also not recommended. Women planning a pregnancy should switch to other blood pressure-lowering drugs to make sure that their blood pressure is well controlled.

“I recommend waiting until you are doing well on these alternative, safer medicines before you try for pregnancy. If you discover you are pregnant in the meantime, never stop any of your medicines without talking to your doctor,” advises Liz.

Pregnancy and birth

Some women with kidney disease may need to give birth by caesarean section—for example, if they develop early pre-eclampsia. However, assuming that all goes well during pregnancy, most women can have a normal vaginal delivery.

Kidney transplantation

Most doctors advise delaying pregnancy for at least one year after a kidney transplant. Liz emphasises that prednisolone, azathioprine, tacrolimus and ciclosporin can all be taken during pregnancy. “If you want to, you can also breastfeed while taking these drugs. Mycophenolate is the only drug that you should absolutely avoid while breastfeeding,” she adds.

Dialysis

Fertility is lower in women on standard three-times weekly haemodialysis or on peritoneal dialysis, but pregnancy is possible. “For this reason, I recommend using contraception if you don’t want to get pregnant on dialysis. If you are on haemodialysis and contemplating a pregnancy—perhaps if a transplant is unlikely in the near future—you can improve your fertility by increasing the amount of your dialysis; do discuss this with your doctor,” says Liz.

To prevent large rises and falls in blood pressure, a woman needs very gentle daily (i.e. six times weekly) dialysis throughout her pregnancy. “This is demanding for a woman, but it does mean a much freer diet and a higher fluid allowance—and she is more likely to give birth nearer term and have a well-grown baby,” comments Liz.

RaDaR pregnancy register

The National Registry of Rare Kidney Diseases (RaDaR) is a Renal Association initiative designed to collect information about certain rare kidney diseases. RaDaR now has a Pregnancy and CKD Group that aims to recruit all UK pregnant women with kidney disease, including those with early CKD (Stages 1 and 2), as well as women on dialysis or with a kidney transplant.

Liz urges pregnant women to register for the Pregnancy and CKD Group, even if they are already included in another RaDaR group. “It is only by collecting real-life data that we are going to get the information that we need to give women up-to-date advice about fertility, pregnancy and kidney disease,” she concludes.