Why Do Some Pregnant Women Get Morning Sickness While Others Don’t?

Pregnant woman with morning sickness

Pregnant woman with morning sickness

When I found out that I was pregnant with my first child, I wanted to throw up. And, I don’t mean because I was upset, scared, or disgusted by the news. Absolutely not.  I was the happiest woman on the face of the earth. For hours, I stared at that long plastic test marked with two dark pink lines overjoyed and excited about the journey I was about to begin.  

In the days following the great news though, I kept waiting for the morning sickness and the nauseous feeling everyone talked about to kick in. I wanted to “feel pregnant.”  I wanted to call my friends and family and share how my pregnancy symptoms were kicking in at full speed, just like some of my “mom friends” had shared with me when they were expecting.

By week 7, I had stocked up on salt crackers and ginger ale. (I had read somewhere on the web that they would come in handy.) I waited patiently every morning, wondering if the need to run to the bathroom and hurl over the toilet would ever come.  It never did. Nothing. No morning sickness once. Not even a little.

“How are you holding up?” a close friend, who was expecting twins, would often ask me. The truth was — I had never felt better.

By week 9, I was eager for my first appointment. I wanted reassurance. An ultrasound. Something!  I mean, urine pregnancy tests don’t lie, right?

Yes. I was pregnant. So when my doctor asked how I was feeling I replied with a different question, “Why don’t I feel nauseous like most pregnant women do?”

“You mean like they do in romantic comedies?” he asked. I hadn’t thought about that, but, yes, in fact. Well, it turns out not all of us will have a moment like actress Katherine Heigl did in the movie “Knocked up.” And, it is perfectly normal.

“Some of it is just how some women react to the elevated HCG levels (Human Chorionic Gonadotropin is a hormone a woman’s body makes during early pregnancy),” says  Dr. Robert Atlas, OB/GYN, Family Childbirth and Children’s Center at Mercy Medical Center in Baltimore, Maryland. “Higher than normal HCG can be due to a multiple gestation.”

No wonder my pregnant friend with twins could hardly keep a meal down.

Also, “abnormal pregnancies can cause significant elevations in HCG. This is particularly true for molar and partial molar pregnancies,” adds Dr. Atlas. Wait, but what is a molar pregnancy?

A molar pregnancy happens when an egg is fertilized, but instead of it resulting in the development of a normal fetus, the placenta develops into an abnormal mass of cysts with no baby.

No need to panic, though, molar pregnancies are quite rare. According to the American College of Obstetrics and Gynecology, approximately 1 out of 1,000 pregnancies results in a molar pregnancy in the United States.

“Some pregnant women who have elevated stress can experience an increase in nausea/vomiting,” points out Dr. Atlas.  So, if you are too worried about checking off items on your “newborn checklist,” take a deep breath and head over to a prenatal yoga class instead.

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