Emily Oster, PhD

2 minute read Emily Oster, PhD
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Emily Oster, PhD

Does IVF Impact Breastfeeding?

Q&A on frozen embryos

Emily Oster, PhD

2 minute read

We’re in the process of deciding what to do with our remaining embryos. While I know you can’t tell me if I want more kids, there are practical questions I am still curious about. If I opt to implant another, I would like to do it in the next few months, but I was also planning on nursing my 18-month-old until he’s 2.

So here are my questions: (1) Are there drugs in the frozen embryo transfer process that would legitimately interfere with breastfeeding? (2) Would breastfeeding, given my period has been back for 12 months, lower my chances of successful implantation? (3) If I do have to defer implantation, is there any reason for me to stick to my “I don’t want to be pregnant after 40,” given that they are eggs from a younger age?

—Two on Ice

I appreciate your pre-empting my speech about how I cannot tell you how many kids to have!

  1. The drugs that are typically used in these cycles could affect your breast milk supply. However, considering how far along you are in breastfeeding, the effects are likely to be small.
  2. We can extrapolate the answer to this question from the question of getting pregnant while nursing in general. In general, breastfeeding acts as birth control by preventing ovulation. Breastfeeding is not contraindicated during pregnancy, including early pregnancy (i.e., implantation). This is reassuring. In addition, we have some small-scale data showing that women who are breastfeeding are just as likely to have a successful IVF transfer as those who are not. Again, reassuring.
  3. No. In the immortal words of Matthew McConaughey in Dazed and Confused: “That’s what I love about these high school girls [read here: frozen embryos], man. I get older; they stay the same age.” You’ve got a little breathing room.
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Parentdatafan84
Parentdatafan84
1 month ago

This is so interesting. I’d love more detail on this. My IVF clinic is saying they want me to wean, they had also said we couldn’t have sex for the first 12 weeks of pregnancy. I’d love more data to see if I can change their minds.

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