The position of the babies will largely determine how the twins are born - vaginally or by cesarean. About 40% of twins are both head down (vertex) at term, another approximately 30% see the first baby (Twin A) vertex and Twin B breech. Both of these positions are acceptable to consider a vaginal birth.
Other positions of the babies like two breeches, two transverse or Twin A breech and Twin B vertex are usually delivered via cesarean surgery. This is usually known ahead of time with ultrasound technology. However, even twins can change positions late in the game and even into labor. This is particularly true of Twin B after the birth of Twin A.
More than half of twins will be born vaginally. Whether this option is the right one for you and your babies is a discussion that should be discussed with your doctor or midwife. The good news is that even though you have two babies - you only have to labor once!
Once the cervix is open, each baby will have it's own pushing stage (second stage). This means you will have to push twice, but the majority of the time the second twin is born much more easily than the first. This is because the first twin has paved the way, so to speak.
The average time between the birth of the first and second baby is generally about 17 minutes. However, as long as the second baby is doing well (they will still be monitoring this baby), there isn't much need to speed things along. Sometimes during this phase of waiting, you will have an ultrasound to confirm the position of the second twin and your practitioner will decide how it is best to deliver him or her.
Sometimes, the second twin simply comes down head first like Twin A, this is handled in exactly the same manner. If Twin B is breech, your practitioner may decide to allow the baby to deliver breech, to turn the baby externally or internally or even do something called a breech extraction (pulling baby out by the feet).
While having twins does increase the risk of you having a cesarean, fewer than half of twins are born this way. While positioning of your babies will play a large part in the decision as to what type of birth you will have, there are also all of the normal reasons for cesareans. These include, placenta previa, placental abruption, maternal indications like PIH, active herpes, and labor complications like fetal distress, etc.
If you give birth by cesarean prior to labor, the date will most likely be set between 37-40 weeks. If you go into labor prior to the scheduled date, your cesarean will likely happen then. There is no real difference in the surgery or recovery from a cesarean with twins.
Combined Vaginal/Cesarean Birth
This is actually not as common as you might believe. One baby being born vaginally with the second twin being born via cesarean occurs in only about 3-4% of all twin births. Usually this is done for an emergency with Twin B, like a cord prolapse (This is where the cord comes out with or before the baby, thereby cutting off the baby's oxygen supply.), severe malpresentation (like a transverse baby that cannot be moved by internal or external forces), placental abruption (This is where the placenta tears away from the wall of the uterus prematurely.), etc.
More than half of twins will be born prior to 37 weeks. This can also impact how your babies are delivered. Talk to your practitioner about staying healthy and maintaining adequate hydration, rest and nutrition to care for your growing babies and body.
Some hospitals require that all twin mothers give birth in the operating room, even if they have a vaginal birth. You might also ask about the use of epidural anesthesia, as it is also sometimes a requirement, even if there are no medications placed inside the tubing. This allows immediate anesthesia should it become necessary. There may be other concerns you have like rooming-in or breastfeeding two babies. Be sure to talk to your hospital at length about issues you may be concerned about with your babies.
No matter how your twins come into the world, be prepared for a sudden change. Be willing to accept help when offered and take the time to get to know each of your new little bundles.