I believe you have to have the maternity insurance in force for one year before becoming pregnant with a lot of these companies, so read the fine print carefully. After paying for a year of insurance, plus continuing to pay during your pregnancy, you can probably save up enough money to cover just paying for the care yourself. The only exception would be if you are considered high risk (and not just because of age) and/or you end up with a c-section.
Another, much cheaper option (than an obgyn) that will give you a wonderful experience and excellent care is going with a Certified Professional Midwife (CPM). I recommend a home bith, but you can do a birthcenter birth too. My midwife was Molly Germash. She was out of of FAmily Birth Services in Grand Prairie, but has now opened her own Birth Center in Peaster (near Weatherford). If that is too far, the other midwives at FBS in Grand Prairie were all really nice. The midwife care I recieved included all basic bloodwork that they do at the beginning of a pregnancy, prenatal care (same schedule as an ob would see you), delivery, newborn exam and pku testing, postpartum checkups at 2days, 2weeks, 6weeks and 12weeks. At 12 weeks you also get your first postpartum pap test done. With my first, born in June 2003, MOlly charged 2,000.00 for all of that. She actually gave us a 400.00 discount though because we were able to pay it all up front. 1,600.00 is pretty hard to beat! With my daughter, born March of 2007, Molly charged 3,000.00. We used her student (which Molly fully supervised) and only paid 2,000.00. Sonograms are an extra 80.00 done by a sonographer that comes to the birth center, which I understand is an excellent amount to pay compared to what dr. offices charge. I would be more than happy to talk to you about my experiences with a midwife if you are new to the idea. I have met quite a few ladies in the time since my first was born and not one person said they won't ever use a midwife again, but almost all have said that about a hospital birth. They all plan on having more home or birth center births in the future. It is very safe and you and your baby will get excellent care!