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Twins Calendar: Weeks 13 through 16

Babies’ Growth
During this month, your babies grow very rapidly, each gaining about three and a half ounces for a total weight of about 4.25 ounces. The body length of each twin can triple to be about 6.5 inches by the end of the 16th week. Your babies’ kidneys will have formed and begin to function, excreting urine into the amniotic fluid. The twins’ heartbeats can also be heard during this month. Your babies move around actively within the uterus, stretching their arms and kicking their legs, but these movements may still be too faint for you to feel.

Mother’s Changes
Between the third and fourth months, your uterus also grows rapidly, rising out of the pelvis. It can be felt halfway between the umbilicus and the pubis by the 16th week. For this reason, many women find that they can no longer wear their normal skirts and slacks, and looser clothing becomes a practical necessity at this time. You may feel the urge to urinate more often because of the pressure of the growing uterus on your bladder. If your doctor has recommended an amniocentesis, it is usually performed between the 14th and 16th weeks. As with a singleton pregnancy, there are certain foods to avoid, such as large fish that contain mercury, sushi, soft cheeses, and deli meats. It can be a confusing time as you ponder whether getting your hair highlighted will also affect the babies. As you begin to prepare for the future, now is a good time to ask your physician for a referral to a lactation consultant. You may want to visit with her again as delivery nears for a refresher course.

Multiple Facts.

  • The biggest disadvantage multiples (as compared to singletons) have is their growth pattern. Whereas an unborn singleton’s weight climbs until 40 week's gestation before slowing down, in multiples, this slowing down of the growth rate occurs much earlier—typically after 34 weeks for twins.
  • Women age 30 or older are significantly more likely to carry their twins for at least 35 weeks than are younger women. 

Diet and Weight Gain
Week 13 marks the beginning of the second trimester—defined as the fourth, fifth, and sixth months of pregnancy. Your twins have now “graduated” from embryo to fetus status. The main difference between the embryonic and fetal periods is that no new organs are being formed. Your babies’ growth is mainly an increase in size. An adequate intake of iron is very important during this middle trimester, as is fiber. Also, take the supplement with food and juice—orange juice, high in vitamin C, helps with iron absorption. Foods rich in iron and the highest source of iron usually come from animals, for example, liver, kidneys, and red meats have the highest levels. If you need to take iron supplements, make sure they contain ferrous sulfate, but remember to drink lots of water and eat raw fruits and veggies for fiber as the supplements often cause constipation. Other sources of iron-rich food include:

  • Fortified dry cereals (Total and Product 19 have 18 mg)
  • Cream of Wheat (8 mg)
  • Beans: red kidney, pinto, black-eyed peas, lentil (between 3 and 5 mg)
  • Apricots (.5 mg per two apricots)
  • Prune juice (4.5 mg)
  • Figs (3 mg per five figs)
  • Raisins (2.5 mg per half cup)
  • Fortified whole wheat breads (.5 mg per slice)
  • Spinach (2 mg iron per serving)
  • Watermelon (3 mg per small slice)
  • Peanut butter (2 mg per four tablespoons)
  • Eggs (2 mg for two eggs)

Eating for Three
Here is a recipe particularly rich in iron and fiber.

Fajita Steak Salad

  • 1/2 pound beef flank steak (or other lean cut of beef)

For fajita marinade and dressing:

  • 1 cup mild taco sauce
  • 1/2 cup canola or flaxseed oil
  • 1/4 cup balsamic vinegar
  • 1 tablespoon fresh chopped cilantro
  • 1 tablespoon fresh chopped jalapeno (optional)
  • 4 green onions, chopped
  • 1 tablespoon cumin
  • Sprinkle of salt and black pepper to taste

For salad:

  • 4 cups romaine lettuce, washed and torn into bite-size pieces
  • 1 cup broccoli florets
  • 1 green pepper, chopped into 1/2-inch pieces
  • 1 red pepper, chopped into 1/2-inch pieces
  • 1/2 red onion, sliced thinly and separated
  • 1/2 cup cooked black beans, drained
  • 1/2 cup chopped cilantro

For crispy tortilla strips:

  • 2-3 whole grain tortillas, cut into 1/4-inch strips
  • Olive oil spray
  • Salt and pepper to taste

1. Combine marinade ingredients in medium bowl with a whisk; pour 1 cup of marinade over steak, save the rest for the dressing. Refrigerate for at least 30 minutes and up to two hours.
2. Toss salad ingredients (except tortilla strips) in a large festive bowl; refrigerate until steak is ready.
3. Spread tortilla strips on a baking sheet. Bake at 350° F for 10 minutes or until lightly browned.
4. Grill or broil steak until medium well-done (160° F when meat thermometer is inserted into thickest part). Discard marinade used on steak.
5. Cut steak into bite-size strips. Serve the meat over the salad with the fajita dressing; top with crispy tortilla strips.