When you’re struggling to get pregnant, you worry about almost everything impacting your chances. This time of year, so many people TTC worry about how cough syrup and other medications affect the body. Like does the flu shot affect ovulation? You'll want to prevent your body from being overcome with mucus like the flu brings, but does any of that affect cervical mucus? It can be quite the mind game, trying to conceive, and worrying about how a vaccine impacts that isn't hard to imagine.
Luckily, the short answer is no, the flu shot doesn’t affect ovulation, according to Dr. Idries Abdur-Rahman, OB-GYN, author of Everything You Ever Wanted to Know About Pregnancy (But Were Too Afraid or Embarrassed To Ask) and one half of the Twin Doctors for TwinDoctorsTV. “Ovulation is driven by the production of hormones from a part of the brain known as the pituitary gland. The pituitary gland produces the hormones FSH and LH, and these hormones stimulate changes in the lining of the uterus to prepare for pregnancy and also stimulate the release of the egg from the ovary — which is ovulation," he tells Romper. "Medications (like birth control pills) that affect the production and release of hormones from the pituitary gland can affect ovulation, but the flu shot does not affect the production of or the levels of these hormones."
So good news, right? You can get your flu shot without worrying about how it will affect your chances of pregnancy. And if you've heard the rumor that taking Mucinex can help ovulation and wonder if the flu shot will do the same, don't hold your breath. Dr. David Diaz, reproductive endocrinologist and fertility expert at MemorialCare Orange Coast Medical Center in Fountain Valley, California, says it’s doubtful. “Human fertility is a complex process involving multiple factors. I am unaware of any component of the vaccine that would impact the ability to achieve a pregnancy if all other factors are normal,” he tells Romper.
And this includes whether you’re conceiving without medication or if you’re getting a little help from IVF or other fertility procedures due to infertility. “Implantation is related to embryo quality and receptivity of the uterus. Neither is impacted by the vaccine,” Diaz says.
However, Abdur-Rahman says there is one sort of roundabout way the vaccine could affect women who are getting IVF. “Some studies do point toward reduced risk of miscarriage in women undergoing IVF who recently received their flu vaccine,” he says.
Abdur-Rahman adds that, so far, it hasn't been proven that the flu vaccine affects conception. “Subfertility/infertility have a wide array of possible reasons, more or less equally spread between male and female causes. Many cases of subfertility are caused by hormonal abnormalities (like Polycystic Ovarian Syndrome), structural issues (like blocked fallopian tubes), or abnormal sperm production. At this time, the flu shot does nothing to affect these conditions.
“The standard thinking at this time is that the flu shot does not in any way affect fertility. As we discussed earlier, there are some studies that point to the flu shot actually increasing fertility transiently by reducing the risk of miscarriage, but the standard thinking right now is that there is no effect, and definitely no ill effect on fertility," he says.
Dr. Mia Di Julio, MD, OB-GYN at Providence Saint John’s Health Center in Santa Monica, California, notes that there are currently clinical trials testing whether the flu vaccine can actually increase the success of IVF — they're thinking the vaccine might "increase the tolerance of a woman's immune system to implantation of the embryo in IVF and then improve success rates.
"It is proposed that the shots are working with the women’s immune system to keep her tolerance to the pregnancy from breaking down too soon," Di Julio tells Romper. "It is thought that if these immune changes occur later in pregnancy, they may also occur early in pregnancy at the time of implantation."
There are of course "arguments against this hypothesis," according to Di Julio. "Arguments suggest that the immune system becomes tolerant to specific molecular markers known as 'antigens' on the embryo during pregnancy, but since the flu vaccine does not have these antigens it would be unlikely to assist in the process of implantation."
In other words: get your flu shot. Don't worry about how it will affect you trying to conceive. The healthier you are, the better.
Dr. Idries Abdur-Rahman, OB-GYN, author of Everything You Ever Wanted to Know About Pregnancy (But Were Too Afraid or Embarrassed To Ask) and one half of the Twin Doctors for TwinDoctorsTV
Dr. David Diaz, reproductive endocrinologist and fertility expert at MemorialCare Orange Coast Medical Center in Fountain Valley, California
Dr. Mia Di Julio, MD, OB-GYN at Providence Saint John’s Health Center in Santa Monica, California