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  • Pregnant with twins & multiples

4 weeks pregnant with multiples

The gestation period is counted from the first day of your last menstrual cycle, which was a few weeks ago. Though you’re in week four now, you probably ovulated (released an egg) about two weeks ago and implantation occurred about a week ago — pregnancy math can be confusing! While it’s just the beginning, some big changes are happening with you and your babies right now. Here’s the lowdown on what you should know when you’re four weeks pregnant multiples!

How are the babies?

The blastocysts (group of cells that will become your babies) have burrowed into the uterine wall, and the outer cells are turning into protective membranes, which will soon fill with amniotic fluid. The exterior cells are also linking with your blood supply and gearing up to start building the placenta.

As the cells rapidly multiply, the inner layers are becoming embryos — this is what your babies are called between 5-10 weeks gestation. While they’re only the size of poppy seeds now, the embryos are growing bigger every day and will eventually develop into babies. As early as four weeks, the neural tubes will begin to form, which will ultimately develop into your little ones’ brains and spinal cords.

What’s new with you?

Let’s talk about pregnancy tests. Week four is around the time when you’ll be missing your period, which means you can take a test. At-home pregnancy tests measure hCG. The hormone starts being released into your body by the developing pregnancy after it implants into the wall of your uterus. Your blood hCG levels will typically double every 48-72 hours throughout the first trimester. Though four weeks can still be too soon for a positive home pregnancy test, those who are pregnant with more than one baby might get a positive sooner because they may have higher levels of hCG early on.

If you have a family history of multiples or transferred more than one embryo during an IVF treatment, you might be anticipating the possibility of more than one baby. Just bear in mind that an ultrasound won’t be able to confirm you’re pregnant with twins or multiples for a couple weeks or so. The good news is that by the time you find out double or triple the fingers and toes are coming your way, you’ll have already been in the pregnancy mindset for a few weeks.

You might start noticing some early pregnancy symptoms in the fourth and fifth weeks, like fatigue, sore breasts, increased cervical mucus, digestive issues, or bloating. With multiples, you may experience more intense symptoms than if you were pregnant with only one baby. But not always, so don’t fret if you’re not feeling particularly intense symptoms.

If you get a positive this week, congrats! Feel free to do a little celebrating. On top of that, make sure you’re taking a prenatal vitamin, and get in touch with your healthcare provider to schedule your first prenatal appointment.

Reviewed by the Ovia Health Clinical Team


Read more

  • 5 weeks pregnant with multiples
  • 6 weeks pregnant with multiples

Sources

  • Mayo Clinic Staff. Fetal development: The 1st trimester. Mayo Clinic. 2020. Web. https://www.mayoclinic.org/healthy-lifestyle/pregnancy-week-by-week/in-depth/prenatal-care/art-20045302.
  • March of Dimes. Amniotic Fluid. 2020. Web. https://www.marchofdimes.org/pregnancy/amniotic-fluid.aspx.
  • MedlinePlus. Fetal development. U.S. National Library of Medicine. 2021. https://medlineplus.gov/ency/article/002398.htm.
  • American Pregnancy Association. What is HCG? 2020. Web. https://americanpregnancy.org/getting-pregnant/hcg-levels-71048/.
  • Singh, N. et al. Role of early serum beta human chorionic gonadotropin measurement in predicting multiple pregnancy and pregnancy wastage in an in vitro ET fertilization cycle. Journal of Human Reproductive Sciences. 2013. Web. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3853879/.
  • Horsager-Boehrer, R. MD. Patience is key: Understanding the timing of early ultrasounds. The University of Texas Southwestern Medical Center. 2018. Web. https://utswmed.org/medblog/patience-key-understanding-timing-early-ultrasounds/.
  • Cleveland Clinic. Expecting Twins or Triplets. 2020. Web. https://my.clevelandclinic.org/health/articles/9710-expecting-twins-or-triplets
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