The essential organs all are under construction and major body parts are in place (legs, arms, head and torso). As the eighth week of pregnancy draws to a close, one more major development unfolds. The embryo gets a final name change, and it is now called a “fetus” until birth.

 

Attention expectant moms: The latest science news warns that you should think twice before taking pain pills. A study published September 2006 in the journal Birth Defects Research Part B found that pregnant moms who took non-steroidal anti-inflammatory drugs (NSAIDs) during their first trimester put their unborn child at risk for developing congenital birth defects—especially heart defects. Popular brands of NSAIDs include Motrin, Advil, Aleve and Celebrex, and the study’s authors are calling for more research to confirm their findings.

Month 3

This is the month of the heartbeat. Using a special tool called a Doppler monitor, doctors can detect the tiny thump-thumps of a 10-week-old fetus.

 

This is also a time of rapid growth inside the womb. By month’s end, the fetus will weight roughly 1 ounce, and it will double in length, uncurling from a tight C-position until it’s about 3 inches long. The tail will disappear and its eyelids, earlobes, limbs and digits will continue to form.

 

Other developmental milestones for this period include thumb-sucking, head-nodding and balling tiny fingers into fists. And though the fetus’s reproductive organs now are under construction, it’s still a bit early for the doctor’s gender declaration. That news (should you want it) usually arrives early in pregnancy’s second trimester.

 

Attention expectant moms: As many as seven out of 10 women suffer morning sickness during the first trimester, according to the Mayo Clinic. But new research conducted by two scientists from the University of Liverpool suggests that poor diet—and not raging hormones—may be the root of your upset stomachs. After reviewing nausea and diet data from pregnant women around the world, the scientists found that women who feasted regularly on sugars, alcohol, oils and meats were more likely to suffer symptoms of “morning sickness” relative to their cereal-munching cohorts. The theory here is that expectant mothers are hardwired to purge their body of hormone-heavy foods (like meats and dairy) in order to protect their vulnerable and growing fetus.

Month 4

Get out the headphones and tune the radio dial to Mozart—this month, the fetus can hear its mother’s heartbeat, her voice and other outside noises. The fetus is also developing at warp speed; by now, all its major organs are complete.

 

In addition, its bones are growing stronger and its muscles longer. Its reflexes also are sharpening up—it can now swallow, kick and execute an occasional somersault with relative ease. And by month’s end, the baby-to-be will weigh around 6 ounces and stretch some 7 inches long. Sweat glands will dot its palms and soles, and its wrinkly skin will shine transparent pink.

 

At this stage, the baby-to-be may look like a complete package, but it still has a few more months of growing to do. By the end of month four, most doctors can perform an ultrasound test and identify the baby’s gender.

 

Attention expectant moms: Got an achy back? A team of Swedish researchers recently concluded that women who participated in water aerobics suffered less back pain (and took fewer sick days at work) compared to women who exercised on land.

Month 5

Finally, the baby really starts kicking! “Quickening” is when a mother senses her potential punter in action for the first time, and this milestone moment usually happens during pregnancy’s fifth month.

 

Also new in this month: hair. The fetus now has tiny white eyelashes and two arching eyebrows. Fine woolly hairs, called lanugo, blanket its body and its bare head also sports a few sprouts.

 

In addition to lanugo, a white, waxy substance called vernix caseosa covers and protects the fetus’s body. And by month’s end, the fetus measures 8 to 10 inches long and tips the scales at 1 pound.

 

Attention expectant moms: Weight gain is a natural—and healthy—part of pregnancy. Doctors recommend adding an extra 300 calories to your daily diet during the second and third trimesters, and mommies-to-be can anticipate gaining anywhere from 15 to 40 pounds during the course of their pregnancy, according to the March of Dimes (and the scale can creep even higher for mothers expecting multiples). But if large numbers like these make you shudder, try asking your doctor to nix the exact figures in favor of referring to your weight gain as simply “healthy” or “unhealthy.”

Month 6

Month 6 marks the end of the second trimester. At this point, the fetus’s essential organs—its kidneys, heart and lungs—are fully formed. The facial features are becoming more recognizable. It also can hiccup and react to loud “outside” noises by blinking, shifting or kicking. By month’s end, the fetus will measure about 12 or 13 inches long and weigh roughly 2 pounds.

 

Attention expectant moms: Pull out the silk sheets and turn up the mood music. Morning sickness is so last trimester. Instead of keeping food down, your biggest struggle this trimester might be keeping your clothes on. By Month 6, your breasts are worthy of a Victoria’s Secret fashion show, and your body is stocked full of the libido-boosting hormone oxytocin.

 

Pregnancy also causes more blood to flow to the vagina, and, in a nutshell, this equals better sex. So go ahead, turn out the lights (or keep them on!) and work your latest assets.

Month 7

The 7-month-old fetus can blink, and its eyes may even remain open for short period of time. Hands and feet are becoming even more active. Also in this phase: Taste buds form and protective fat tissue makes its debut. The fetus’s hearing is fully developed and, in boys, its testicles have moved to the groin. By month’s end, the baby-to-be will measure 14 to 16 inches long and weigh anywhere from 2 ½ to 3 ½ pounds.  

 

Attention expectant moms: During pregnancy, stress may be a double-edged sword. Autism rates are higher among children whose mothers experienced severe stress during their pregnancy, particularly in weeks 25 to 28, according to a study published in the Journal of Autism and Developmental Disorder.

 

But, according to another study conducted by John Hopkins University and the National Institute of Child Health Development, moderate stress may actually benefit a developing fetus. This study found that children born to healthy women who had experienced mild to moderate stress during their pregnancy exhibited superior motor and mental skills at age 2.

Month 8

This month, the fetus’s brain develops rapidly, and all of its organs except the lungs are mature. An 8-month-old fetus stretches 16 to 18 inches long and weighs between 4 and 6 pounds. And as the baby-to-be grows larger, space in the womb becomes scarce. Expectant mothers should still count on catching a few elbows every day, but the elaborate somersault sequences should stop until delivery day. Other exciting changes during this period? The fetus’s fingernails now reach beyond its fingertips and its skin is starting to smooth.  

 

Attention expectant moms: Next time you start worrying that your baby will arrive with 12 toes and two noses, relax. The statistics are in your favor. Between 96 and 97 out of every 100 babies are born healthy, as reported on the Web site for Children’s Hospital Boston’s. And even when babies are born with defects, doctors can often easily cure or correct the issue (as in the case of webbed toes or an extra pinkie finger).